layerman: switch to new meta-minnow repo

Signed-off-by: Koen Kooi <koen@dominion.thruhere.net>
Fix warnings about meta-raspberrypi during update

As pointed out by tasslehoff on IRC it should probably be:
	danny,HEAD
and not:
	master,danny
in layers.txt.
Merge remote-tracking branch 'origin/angstrom-v2012.12-yocto1.3'